1. Field of the Invention
The invention relates to formation of metal capacitors and integrated coaxial lines using a directed source of energy, and in particular to a method and device for forming metal capacitors and integrated coaxial lines using laser or other energy transfer so as to cause conductive links between metals.
2. Background of the Technology
It is known in the art to form interconnecting conductive links between adjacent or closely situated conductive materials, such as for forming conductive paths within nonconductive environments or to produce conductive paths in integrated circuits for a single layer or level.
In forming such conductive paths, it is known to embed metals in nonconductive material and then to apply directed laser pulses at the metals. The metals absorb the pulsed energy and expand, fracturing the nonconductive material and generally forming fracture paths between each of the two most closely situated metals. As the metals absorb further energy, the metals melt or otherwise expand into the fracture areas, so that conductive links form between the closely situated metals. It is known in the prior art to use such methods to form conductive connections within up to two levels of metals. However, it is not known to use conductive paths to form enclosing paths among three or more levels, such as for use in forming integrated coaxial lines or metal capacitors.
The present invention includes a method and device for forming metal capacitor and integrated coaxial lines using laser pulses or other energy transfer so as to cause conductive links between metals among three or more levels, including connected paths enclosing lines within the paths. In one embodiment, metals or other conductors are embedded within nonconductive layers, such that the conductors form a matrix of three levels, each of the levels being separated by nonconductive material, and, within each level, conductors being separated from each other by nonconductive material. In one embodiment, a source of energy is directed at the conductive and nonconductive material, such that at least one conductor is wholly shielded by at least one other conductor, and such that some conductors are partially shielded. Upon absorbing energy, the conductors in this embodiment form conductive paths sequentially among layers, such that closed paths form about at least one shielded conductor. Sequential conductive path formation is encouraged using several methods, such as by 1) exposing differing surface areas of conductors to the directed energy, 2) using diffusion barriers to increase energy absorption, 3) varying relative distances between conductors, 4) employing a metal or other conducting substance having a lower melting point for some of the conductors to encourage formation of links with these conductors first, 5) directing the energy, such as in pulses, so that the energy is transmitted at or to conductors in a particular order or in selected patterns, and 6) combinations of these methods.
In another embodiment, links among differing layers are formed using more than one energy source or sequentially generated and directed pulses of energy.
To achieve the stated and other advantages of the present invention, as embodied and described below, the invention includes method for forming a shielded conducting structure, comprising: directing at least one directable source of energy at a plurality of components, the plurality of components including at least a first layer, a second layer, and a third layer, wherein each of the layers includes conducting and nonconducting portions, wherein at least one of the conducting portions in at least one of the layers is shielded from the at least one directable source of energy by at least a second conducting portion in at least one of the layers when the at least one directable source of energy is directed at the plurality of components, and wherein the at least one directable source of energy is directed so as to impinge the layers sequentially; at least one of the conducting portions in the third layer expandably forming first conductive paths with at least two of the conducting portions in the second layer upon the at least one directable source of energy being directed therat; and the at least two of the conducting portions in the second layer expandably forming second conductive paths to the at least one of the conducting portions in the first layer upon the at least one directable source of energy being directed therat; wherein the first and second conductive paths enclosably surround the at least one shielded conducting portion.
To achieve the stated and other advantages of the present invention, as embodied and described below, the invention further includes a device for forming a shielded conducting structure, comprising: a directed source of energy; a first layer positionable for first receiving the directed source of energy, the first layer having a first layer conducting component and two first layer nonconductive regions adjacent the conducting component; a second layer separated from the first layer by a nonconducting region, the second layer including three conducting components separated by two nonconductive regions, wherein the three conducting components of the second layer include a second layer first conducting component, a second layer second conducting component, and a second layer third conducting component, wherein the second layer second conducting component is located between the second layer first conducting component and the second layer third conducting component, wherein the second layer second conducting component is shielded from the source of energy by the first layer conducting component, and wherein the second layer first conducting component and the second layer third conducting component are at least partially unshielded from the source of energy; and a third layer separated from the second layer by a nonconducting region, the third layer including a third layer conducting component at least partially unshielded from the source of energy, the third layer conducting component extending such that the third layer conducting component is impactable by the source of energy via both of the two nonconducting regions of the second layer.
Additional advantages and novel features of the invention will be set forth in part in the description that follows, and in part will become more apparent to those skilled in the art upon examination of the following or upon learning by practice of the invention.